Self-aligning gear mounting



` A 2 1 s Aug 927 R. CHILTON.

SELF ALIGNING GEAR MoUNTlNG' 3 Sheets-Sheet 1 Filed May 14. 1926 Aug. 2,1927.

'R. CHILTON SELF ALIGNING GEAR` MOUNTING .'5 Sheets-Sheet 2 Filed May14. 192ey `v 1,631 sos Aug. 2, 19,27. R CHILTON SELF ALIGNING GEARMOUNTING Filed May 14; 192e -3 sheetsshee' `3 5 /Z Z/, Z/`

u mmm/2 Patented Aug.- 2, 1927.

"UNITED 4STATE-sl :ROLANDv CHILTON, OF KEYPORT, NEW l'ERSEY, ASSIGNO T0HALYeAEROMABm PATENT-'orrlcaj BUS COMPANY, I NC., A CORPORATION FNEW`YOBK.

Asnnr-macminer am MOUNTING.

pplication leii Hay 14, 1926. Serial No. 109,108.

This invention relates to self-aligning gear mountings and the primaryobject is to provide simple, compact and veasily fabricated -means formaintaining even pressure distri( 'f 6 bution across the width of gearteeth in spite of deiections of the gears or supporting housings underload. Such deflections often prevent increased strength being realizedin practice from 'an increased tooth width, by

` l0 :inducing corner failure from the concentration of load at one endof the teeth.r Torf sional and bending deiections in long or overhungpinions and disalignment from unequal stiness or loading of bearingsupports are lfamiliar exam les, and the latter condition commonlyobtalnsl when the torque reaction from a gear housing vis taken bsupporting means not structurally symmetrical with the gear shaftbearings. In compound gear trains it is diicult toinsure deectionalsymmetry especially as the relative bearing deflections within a complexcasing are difficult to estimate.

The prior art shows relatively elaborate 25 pivoted subrames for thebearings to-comensate for theseminutedeflections and this invention aimsat providing relatively simple means for this purpose.

For the urpose of this disclosure, a gear train suita le for an enginestarter is shown as illustrating the foregoing .considerations in amechanism wherein compactness, lightness and simplicity of constructionare desired.

In `the drawings:

Figure 1 1s a vertlcal section ofa compound gear train embodying thepresent in* vention. 4

F1 re'2 1s a transverse sectlon taken on the line 2 of'Fig'. 1 lookingin the direction prising a gear 11, and a pinion :1.2, supported inbearings 2O and 21. lThe gear is prefu erably centrally supported on abearing 19 directly engaged in the housing 8'. Special features of thisinvention relate to the cy;

lindrical sleeve 13 supporting the pinion bearings 20 and 21 and in turnsupported by i a relatively short abutment 16 in the housing disposedsubstantially opposite' to the midwidth of the teeth. This abutmentconveniently takes the form lof a narrow'rib projecting into thehousingjand bored to it the outer diameter of the sleeve 13, and cutyaway 4on one side, as is the sleeve (at 24.in

Fig. 6), to .clear the4 ear 11.

The toothloads an' bearing reactions are resisted only at the relativelynarrow and centrally disposed contact between the sleeve 13 andtheabutment 16 whereby the tooth pressures at either endv of the teeth mustbe 1n equilibrium since the sleeve acts-as a centrally supportedcompensatin leverfor'this purpose. Spherical orpivota ly formedcontactsurfaces between the sleeveand the case may be used if substantialangular deiiections are apprehended, but in general -the- Amore simplyformed and assembled short cylindrical support shown, willA be incapableof exerting subtsantial resistance to the minute tilt necessary -toenable the teeth to' I remain in strictly parallel contact. To this end,excessive tightness in the it ofthe sleeve tothe casing is to beavoided.

Although the center of. the sleeve 13 and its abutment '16 inthe'housingare partly cut away on one side to clear the gear, it

vwill- ,be seen that the direction of load on the pinion bearings isaway from the opening 24 and tends to keep thesleeve againstl theuninterrupted side of vthe supporting surface. l.A locating screw17-hav-1ngaspringwasher' 18 may be used to locate the sleeve 13 endwise.

In the case of a double 'reduction gear train some reaction from theiirst'reduction gear 9 and pinion 10 devolves upon the-sleeve 1 3, Asuchreaction being always proportional to the tooth loads, and equilibriumofthe sleevecarried parts is maintained by slightly oft'- settingA themidwidth of the vsleeve-supporting abutment from the center of thewidth' ofthe second reduction pinion.

In additionl to disturbances from deecetions'of its own bearings, thefirst reduction 'by a simi fpi'non 10-sh0uld be tofollow any angu# Il:lar deflection of the second reduction pinion assemble This freedommay be provided i ar floating sleeve and narrow abutment asalready-described, butas one of the `pinion' bearings may be 'moreconveniently supportedfrolnanother gear'shaft as 1n the vinstance of theshowing, alternative selfmeans are included in this invenm l i sAccordingly, the iirst reduction gear 9 1s mounted on a lay shaftcomprising the seczol with a locating face on the cover of theNAportion, a toothed pinion having bearings' housin corresponding parts.from these figures preferably the gear 9.-

ond' reduction pinionv 12. This (gear is provided with a hub 25 havlngen splines 26 engaged by splines 27 conveniently com rising extensionsof the pinion teeth 12. oth the top of the tooth extensions and theouter diameter of the end s lines of the gear 9 are preferably fitted tot e bore `of the bearing 20 so that both the v.gear and the pinionaredirectly centered in the bearing which is disposed midway of the widthIof A cylindrical-extension 23 of the pinion-shaft may be fitted-to abore'in the hubsplines 26, but the Yfitted length should. be short topermit slight angularity in the plane of the gear "9 relative to theinion to enable the teeth of thefo'rmento ollow any angular deiection ofthe pinion' 10. For the same reason end location of the gear hub 25 uponthe inion extension 23, is preferably effected ov y by loose contact asOveiung pinions are specially'subject to deiiection vcausing detrimentalconcentration of load at one end of the teeth and-Figs. 4 and 5explainthe application of this 1nvention to such cases." n these '-lires the exponent a has been added to t e reference numeral previouslyusedV to indicate the It will be -obvious that by the use of thisinvention the spacin of the 'bearings need not be symmetrical wlth the'gear width' since `the sleeve will balance the gear tooth reactions ainst 'a centrally located abutment through arin having any convenientoilsdisposltion, and one of the features'of this invention resides incompensating theV deilectons which otherwise may prohibit theygioften.more convenient, o verhung pinion. construction. Fi 5 shows indiagrammaticformfthat the pinion, sleeve, and bearing assemblage 'are,analogous in eiect to' a 'leverbent-backf upon itself whereby a forceapplied at fone lend may be balancedv against an abutment contactin withthe other regardless of the amount o oset in the lever intermediate itsadjacent ends.

Variations may be resorted to within the scope of the invention andportions of the improvements may be used without the others, whilst notdeparting from the spirit' of the-invention. f

Having thus described my invention, I claim:

1. In apparatus of y combination of a, housing, a lay lshaft com-lprising a ear and pinion drivably connected for sli ing width thereof',a bearing for the pinion, and a mounting ported forV housing.

2. In a gear train, the combination of a lay shaft com rising a toothedpinion mounted for slig t tiltmg action, a gear hav-, 1n th pinion.disposed at the midwidth thereof.'

3. In a gear lay shaft comprising a toothed -Y pinion, a gear havingsplines engaged with an end of the pinion teeth, and a bearing for theear disposed at the mid-width sai spline engagement..

4. In a ar train', the combination with av housing, o a gear, a pinion,means driwably vconnecting said gear and pinion for slight drivingsplines engagedk with an end of" teeth,and a bearing for the gear theclass described, the

sleeve for said bearings s p slight tilting action in t eltrain, thecombination of a u thereof anda ut l tilting action relativegeach other,and means for .mounting'both in the. housing for tary tiltingY actionrelatively thereto.

' 5. Ina gear train, casing having a narrow circular rib portion,

' asleeve rock'ably supported against said rib pinion forrotationtherewith .in sucha manrmi't .of slight angular deflections 'ofthe classdescribed, um combmation of a casing, a sleeve member.-

ner as to relative t creto.

- '7.-`In` apparatus mounted in the casing for slight angulardeviiections of its axis, bearings supported in said sleeve, a pznionmounted in said bearings, 'a gear havinga hub drivably'connected to theplmon in 'a manner as to permit of 'lshght angular deections thereofrelative to wiet having driving splines engage with an endv of the disose mi -width of the gear,v a further support of said bearings; 'saidsleevebemg the combination of `a 8.Y Ina gear train, the combination ofa lay shaft comprising a toothed (pinion, la gear ub extending into 12aVsaid inion; said connection being within vthe f pinion teeth, a bearingfor the 'gear at Aone end ofthe pinionand at thel bearing at' 1 theother end of the pinion, a sleeve for the mounted to per-mit of slight'angular deections of its axis.

9. vA self ali shaft an engaging the projections on the gear hub; saidengagementbeing within the width of the gear, and a bearing fitted overYsaid projections.

10. In a ear train, a pinion, av gear, a splined driving connectiontherebetween engaged Within the width of the .gear teeth, a casinghaving a circular rib portion adjacent the mid-portion of the pinionteeth and ing mounting for a gear, upon a plnion s aft comprlsing incomblnaa housing having pinion'bearings and en.

gagingvsaid rib portion. 11. A self-aligning gear mounting comprising, apinion, a gear, a splined connection therebetween within the width ofthe gear Jface, a gear casing having a circular rib portion adjacent themid-Width of the pinion, and a rocha-ble supporting sleeve engaged withsaid rilo portion and having bearings for the support of the pinion, oneof which engages said splined connection. Signed at'Keyport, in thecounty of Monmouth, and State of New Jersey this 13th day of May A. D.1926.

ROLAND CHILTON.

